We have grouped, under this title, what has been ascertained as certain damage to the health of bees or other pollinating insects.

Millions of bees have mysteriously disappeared around the world in the 1880s, 1921, 1960s.

For mysterious viruses ? The cause of these disappearances has been attributed to viruses and environmental factors, especially pesticides. However, the cause has not yet been discovered.

The phenomenon of the mysterious disappearance of bees in different historical periods, such as the 1880s, 1921, and the 1960s, can be examined in more detail by considering the various environmental, agricultural, and biological factors involved:

1880s - During this period, agricultural practices were rapidly changing with the introduction of industrial methods. There are no specific records of a massive decline in bees, but it's likely that the onset of pesticide use and loss of natural habitats had an impact on their populations.

1921 - In this time, bees began to suffer from the consequences of diseases like nosema (a disease caused by a parasitic fungus) and the varroa mite, a parasite that harms bees. The use of chemical pesticides in agriculture was also becoming more common, which might have contributed to the decline of bees.

1960s - This decade saw a significant increase in the use of pesticides like DDT, known to be harmful to bees. Additionally, monoculture and intensive agricultural practices reduced biodiversity and the availability of flowers and plants beneficial to bees. These factors, combined with diseases and parasites, likely contributed to the decline in bee populations.

In general, the decline in bees is often the result of a combination of factors, including pesticide use, habitat loss, diseases, and climate change. While there have been cases of viruses affecting bees, such as the deformed wing virus, there is no evidence that a single "mysterious virus" was the main cause of these historical bee decline events.